Bone marrow transplant has now been expanded to include other sources of stem cells, thus the emergence of the use of the term hematopoietic stem cell transplant, as it includes stem cells from sources other than the bone marrow. Cytotoxic myeloablative therapy (chemotherapy and radiation intended to destroy bone marrow and to make room for new cells through a transplant) destroys the mucosa of the intestinal tract, impairing functions of the epithelium that are essential to health. Enteral nutrition (taking nutrients from food via the intestinal tract) is essential for the mucosa to adequately absorb nutrients from food. Enteral nutrition promotes the structural integrity of the gut. The provision of enteral nutrition during chemotherapy has protective effects on the gut, and the provision of early enteral feedings has a beneficial effect on complication and sepsis rates after surgery. Since hematopoietic cell transplant recipients experience many of the factors that facilitate movement of bacteria into the bloodstream, invasion by enteric microorganisms might commonly occur in this population. Therefore, early enteral feeding to restore the mucosa can be expected to decrease bacterial translocation and its consequences. The specific aims of the study are to investigate the safety and feasibility of early enteral feeding in pediatric cell transplant patients. Secondary and long term goals of this study are to (1) describe the clinical impact of early luminal feedings on oral intake, (2) describe the physiologic impact of early luminal feedings on cytokine production, and (3) describe the physiologic impact of early luminal feedings on bacterial translocation.